Phagocytosis, one of the most powerful ways to eliminate invading pathogens in innate immunity, is conserved in vertebrates and invertebrates. PF 429242 During the phagocytosis process, many proteins are found to be involved in its regulation. In recent years, the roles of microRNAs in the regulation of phagocytosis have attracted more and more investigations. However, the mechanism of miRNA- mediated regulation of phagocytosis is not intensively studied. On the basis of our previous investigation, in this study, the results revealed that miR-1, a sequence-conserved miRNA in animals, took great effects on the negative regulation of phagocytosis of shrimp hemocytes and murine macrophage RAW264.7 cells. Our GNE-317 findings indicated that the sequence-conserved miRNA in vertebrates and invertebrates might share similar or same functions in animal immunity. Invertebrates including shrimp lack a true adaptive immune response system and have developed an effective nonspecific innate immune response for detecting and eliminating noxious microorganisms. As reported, phagocytosis plays an essential role in shrimp immunity. In this context, shrimp could be served as a good candidate to reveal the regulation of phagocytosis mediated by miRNAs. It is reported that microRNAs can regulate diverse biological processes by targeting the mRNAs of target genes. In this study, the data presented that miR-1 was involved in the regulation of phagocytosis through the interaction between miR- 1 and the 39 UTR of clathrin heavy chain 1 gene. Clathrin consists of three heavy and three light chains. Clathrincoated vesicles are mainly involved in mediating internalization of many cell surface proteins from the plasma membrane and returning some of them through recycling endosomes back to the plasma membrane. In phagocytosis, the occupied receptors on cell surface of phagocyte activate a signaling cascade that leads to actin polymerization, plasma membrane remodeling, and extension of pseudopods around the particles. The receptor/ membrane recycling takes place through a clathrin-mediated endocytic pathway. During the phagocytosis process, clathrin can be recruited to the phagocytic cup in modest amount.